GLASS GUY:Bryan Brooks (left), with a lawyer, was cleared yesterday. At right, Chaka Smith bears a huge scar on his face where a fellow bar patron allegedly slashed him with a broken glass in a fight. (
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This Manhattan lawyer can now pop the champagne, but he might want to use a paper cup.

A former attorney for American Express was fully acquitted yesterday of bizarre felony assault charges that could have put him in prison for 25 years — for allegedly gashing a rival in the face with a broken champagne flute during a brawl at SoHo’s tony Thom Bar at the Thompson Hotel last summer.

Jurors cleared Columbia Law School grad Bryan Brooks, 37, in the froufrou fracas after the lawyer testified that it was his much-larger, much-more-drunken supposed victim who had started it.

“I was scared,” Brooks had told the jury of standing there under the chandeliers, flute in hand, only to be shoved in the chest for no apparent reason by a stranger.

“He had already hit me twice. And I just swung,” Brooks had told jurors.

“I was holding the champagne glass from which I was drinking. All I remember was trying to get this big guy off of me.”

Chaka Smith, a 27-year-old real estate manager who had admitted downing nine or 10 drinks that night, needed 50 stitches to close the gaping wound to the left side of his face.

Smith also had taken the stand earlier this week, showing jurors the scar that crosses from his cheek to his neck.

Smith gave jurors a far different version of events — one in which it was Brooks who went berserk for no reason while demanding, “Are you laughing at me?”

“He asked me if we were laughing at him,” Smith testified of sitting on a couch at the end of the bar, with his friend Dominique. Her sister had dated Brooks, and there had been some bad blood, Smith said.

“I was leaning into her while she spoke,” Smith testified. They’d been looking in Brooks’ general direction, he remembered.

Smith remembered standing and answering the angry, smaller man, “I don’t know you — why are we even talking?” Then the two started shoving each other in the chest, he remembered. He didn’t even feel the glass hit him, he told jurors.

“What I felt like was a smack. On my face,” he said.

But Brooks lawyer Eric Seiff had told jurors in closing arguments that Brooks had swung in self-defense, and that Smith’s injuries could have been caused by the glass on the floor from a giant ice bucket filled with bottles and glasses that had toppled in the fray.